Re: [PATCH] net: wget: Avoid packet queue overflow

[Richard Weinberger <richard@nod.at>]

----- Ursprüngliche Mail -----
> Von: "richard" <richard@nod.at>
> An: u-boot@lists.denx.de
> CC: "richard" <richard@nod.at>, "Joe Hershberger" <joe.hershberger@ni.com>, "Ramon Fried" <rfried.dev@gmail.com>
> Gesendet: Donnerstag, 20. Juli 2023 14:51:56
> Betreff: [PATCH] net: wget: Avoid packet queue overflow

> Make sure to stay within bounds, as a misbehaving HTTP server
> can trigger a buffer overflow if not properly handled.
> 
> Cc: Joe Hershberger <joe.hershberger@ni.com>
> Cc: Ramon Fried <rfried.dev@gmail.com>
> Signed-off-by: Richard Weinberger <richard@nod.at>
> ---
> net/wget.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/net/wget.c b/net/wget.c
> index 2dbfeb1a1d5b..8bb4d72db1ae 100644
> --- a/net/wget.c
> +++ b/net/wget.c
> @@ -35,7 +35,8 @@ struct pkt_qd {
>  * The actual packet bufers are in the kernel space, and are
>  * expected to be overwritten by the downloaded image.
>  */
> -static struct pkt_qd pkt_q[PKTBUFSRX / 4];
> +#define PKTQ_SZ (PKTBUFSRX / 4)
> +static struct pkt_qd pkt_q[PKTQ_SZ];
> static int pkt_q_idx;
> static unsigned long content_length;
> static unsigned int packets;
> @@ -202,6 +203,13 @@ static void wget_connected(uchar *pkt, unsigned int
> tcp_seq_num,
> 		pkt_q[pkt_q_idx].tcp_seq_num = tcp_seq_num;
> 		pkt_q[pkt_q_idx].len = len;
> 		pkt_q_idx++;
> +
> +		if (pkt_q_idx >= PKTQ_SZ) {
> +			printf("wget: Fatal error, queue overrun!\n");
> +			net_set_state(NETLOOP_FAIL);
> +
> +			return;
> +		}
> 	} else {
> 		debug_cond(DEBUG_WGET, "wget: Connected HTTP Header %p\n", pkt);
> 		/* sizeof(http_eom) - 1 is the string length of (http_eom) */

Friendly ping. :-)

Thanks,
//richard